Robotic surgical system and method

ABSTRACT

The present invention provides an apparatus, system and method for providing robotically assisted surgery that involves the removal of bone or non-fibrous type tissues during a surgical procedure. The system utilizes a multi-axis robot having a reciprocating tool that is constructed and arranged to remove hard or non-fibrous tissues while leaving soft tissues unharmed. The multi-axis robot may be controlled via computer or telemanipulator, which allows the surgeon to complete a surgery from an area adjacent to the patient to thousands of miles away.

CROSS REFERENCE TO RELATED APPLICATIONS

In accordance with 37 C.F.R. 1.76, a claim of priority is included in anApplication Data Sheet filed concurrently herewith. Accordingly, thepresent invention claims priority as a continuation of U.S. patentapplication Ser. No. 15/816,861, filed Nov. 17, 2017, entitled “ROBOTICSURGICAL SYSTEM”; which claims priority to U.S. Provisional PatentApplication No. 62/423,677, filed Nov. 17, 2016, entitled “ROBOTICSURGICAL SYSTEM”, which also claims priority to U.S. Provisional PatentApplication No. 62/423,624, filed Nov. 17, 2016, entitled “ROTARYOSCILLATING SURGICAL TOOL”; and which also claims priority to U.S.Provisional Application No. 62/423,651, filed Nov. 17, 2016, entitled“ROBOTIC SURGICAL SYSTEM”; which is a continuation-in-part of U.S.patent application Ser. No. 13/469,665, filed May 11, 2012, entitled“ROTARY OSCILLATING BONE, CARTILAGE, AND DISK REMOVAL TOOL ASSEMBLY”.The contents of each of the above referenced applications are hereinincorporated by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to surgical systems and, moreparticularly, to a multi-axis robotic device having an end effectorconstructed to remove bone and non-fibrous tissues while minimizingdamage to soft tissue.

BACKGROUND OF THE INVENTION

The central nervous system is a vital part of the human physiology thatcoordinates human activity. It is primarily made up of the brain and thespinal cord. The spinal cord is made up of a bundle of nerve tissuewhich originates in the brain and branches out to various parts of thebody, acting as a conduit to communicate neuronal signals from the brainto the rest of the body, including motor control and sensations.Protecting the spinal cord is the spinal, or vertebral, column.Anatomically, the spinal column is made up of several regions includingthe cervical, thoracic, lumbar and sacral regions. The cervical spine ismade up of seven vertebrae and functions to support the weight of thehead. The thoracic spine is made up of twelve vertebrae and functions toprotect the organs located within the chest. Five vertebrae make up thelumbar spine. The lumbar spine contains the largest vertebra andfunctions as the main weight bearing portion of the spine. Located atthe base of the spine is the five fused vertebrae known as the sacrum.The coccyx sits at the base of the spinal column and consists of fourfused vertebrae.

Each of the vertebrae associated with the various spinal cord regionsare made up of a vertebral body, a posterior arch, and transverseprocesses. The vertebral body, often described as having a drum-likeshape, is designed to bear weight and withstand compression or loading.In between the vertebral bodies is the intervertebral disc. Theintervertebral disc is filled with a soft, gelatinous-like substancewhich helps cushion the spine against various movements and can be thesource of various diseases. The posterior arch of the vertebrae is madeup of the lamina, pedicles and facet joints. Transverse processes extendoutwardly from the vertebrae and provide the means for muscle andligament attachment, which aid in movement and stabilization of thevertebra.

While most people have fully functional spinal cords, it is not uncommonfor individuals to suffer some type of spinal ailment, includingspondylolisthesis, scoliosis, or spinal fractures. One of the morecommon disorders associated with the spinal cord is damage to the spinaldiscs. Damage to the discs results from physical injury, disease,genetic disposition, or as part of the natural aging process. Discdamage often results in intervertebral spacing not being maintained,causing pinching of exiting nerve roots between the discs, resulting inpain. For example, disc herniation is a condition in which the discsubstance bulges from the disc space between the two vertebrae bodies.It is the bulging of the disc material which causes impingement on thenerves, manifesting in pain to the patient. For most patients, rest andadministration of pain and anti-inflammatory medications alleviates theproblem. However, in severe cases, cases which have developed intospinal instability or severe disc degeneration, the damaged discmaterial between the vertebral bodies is removed and replaced withspinal stabilization implants. Restoration to the normal height allowsthe pressure on the nerve roots to be relieved.

There are many different approaches taken to alleviate or minimizesevere spinal disorders. One surgical procedure commonly used is aspinal fusion technique. Several surgical approaches have been developedover the years, and include the Posterior Lumbar Interbody Fusion (PLIF)procedure which utilizes a posterior approach to access the patient'svertebrae or disc space, the Transforaminal Lumbar Interbody Fusion(TLIF) procedure which utilizes a posterior and lateral approach toaccess the patient's vertebrae or disc space, and the Anterior LumbarInterbody Fusion (ALIF) which utilizes an anterior approach to accessthe patient's vertebrae or disc space. Using any of these surgicalprocedures, the patient undergoes spinal fusion surgery in which two ormore vertebrae are linked or fused together through the use of a bonespacing device and/or use of bone grafts. The resulting surgeryeliminates any movement between the spinal sections which have beenfused together.

In addition to the spinal implants or use of bone grafts, spinal fusionsurgery often utilizes spinal instrumentation or surgical hardware, suchas pedicle screws, plates, or spinal rods. Once the spinal spacersand/or bone grafts have been inserted, a surgeon places the pediclescrews into a portion of the spinal vertebrae and attaches either rodsor plates to the screws as a means for stabilization while the bonesfuse. Currently available systems for inserting the rods into pediclescrews can be difficult to use, particularly in light of the fact thatsurgeons installing these rods often work in narrow surgical fields.Moreover, since patients can vary with respect to their internalanatomy, resulting in varying curvatures of the spine, a surgeon may notalways have a linear path or may have anatomical structures that must bemaneuvered around in order to properly insert the surgical rods into thepedicle screw assemblies. In addition to requiring surgical skill,difficulty in placing the rods correctly into the pedicle screws canresult in unnecessary increases in the time it takes a surgeon tocomplete the surgical procedure. Prolonged surgery times increase therisk to the patient. More importantly, improperly aligning the rods andpedicle screw assemblies often results in post-surgery complications forthe patient and requires corrective surgical procedures.

Robotic surgery, computer-assisted surgery, and robotically-assistedsurgery are terms for technological developments that use roboticsystems to aid in surgical procedures. Robotically-assisted surgery wasdeveloped to overcome the limitations of pre-existing minimally-invasivesurgical procedures and to enhance the capabilities of surgeonsperforming open surgery.

In the case of robotically-assisted minimally-invasive surgery, insteadof directly moving the instruments, the surgeon uses one of two methodsto control the instruments; either a direct telemanipulator or throughcomputer control. A telemanipulator is a remote manipulator that allowsthe surgeon to perform the normal movements associated with the surgerywhile the robotic arms carry out those movements using end-effectors andmanipulators to perform the actual surgery on the patient. Incomputer-controlled systems, the surgeon uses a computer to control therobotic arms and its end-effectors, though these systems can also stilluse telemanipulators for their input. One advantage of using thecomputerized method is that the surgeon does not have to be present, butcan be anywhere in the world, leading to the possibility for remotesurgery. One drawback relates to the lack of tactile feedback to thesurgeon. Another drawback relates to visualization of the surgical site.Because the surgeon may be remote or the surgery may be percutaneous, isit difficult for the surgeon view the surgery as precisely as may beneeded.

In the case of enhanced open surgery, autonomous instruments (infamiliar configurations) replace traditional steel tools, performingcertain actions (such as rib spreading) with much smoother,feedback-controlled motions than could be achieved by a human hand. Themain object of such smart instruments is to reduce or eliminate thetissue trauma traditionally associated with open surgery. This approachseeks to improve open surgeries, particularly orthopedic, that have sofar not benefited from robotic techniques by providing a tool that candiscriminate between soft tissue and hard or non-fibrous tissue forremoval or modification.

There exists, therefore, a need for a robotic system that can be used bya surgeon to easily and safely remove or modify bone, cartilage and diskmaterial for orthopedic procedures, particularly but not limited to thespine. The robotic surgical system should provide ultrasoundcapabilities to provide the surgeon with the capability of visualizationand/or real time visualization of the surgical field.

BACKGROUND

The prior art has provided rotary bone, cartilage, and disk removal toolassemblies. A problem with rotary bone, cartilage, and disk removal toolassemblies is caused by an encounter with fibrous material, which maywrap about a rotary cutting tool and cause unwanted damage. The priorart has also provided rotary oscillating bone, cartilage, and diskremoval tool assemblies. However, due to the high risk of damage to apatient, surgical procedures that are assisted or completed through theuse of multi-axis robots in combination with rotary bone or non-fibroustissue removal tools have remained unused.

SUMMARY OF THE INVENTION

The present invention provides an apparatus, system and method forproviding robotically assisted surgery that involves the removal of boneor non-fibrous type tissues during a surgical procedure. The systemutilizes a multi-axis robot having a reciprocating tool that isconstructed and arranged to remove hard or non-fibrous tissues whileleaving soft tissues unharmed. The multi-axis robot may be controlledvia computer or telemanipulator, which allows the surgeon to complete asurgery from an area adjacent to the patient to thousands of miles away.The system also provides ultrasound, also referred to as sonography, todevelop real time images of the surgical field to assist the surgeon insuccessfully completing the surgery.

Accordingly, it is an objective of the present invention to provide anoscillating tool that can be used in combination with a multi-axis robotto remove bone.

It is another objective of the present invention to provide anoscillating tool that can be used in combination with a multi-axis robotto remove non-fibrous tissue.

It is a further objective of the present invention to provide anoscillating tool that can be removably secured to the distal arm of amulti-axis robot to allow the oscillating tool to be interchanged withother tools.

It is yet another objective of the present invention to provide anoscillating tool that can be utilized on robots having variousconstructions.

It is a still further objective of the present invention to provide anoscillating tool that utilizes a removable and replaceable cutter.

Yet another objective of the present invention is to provide a roboticsurgical system that utilizes ultrasound to provide real time images tothe surgeon completing or controlling the robotic surgery.

Still yet another objective of the present invention is to provide arobotic surgical system wherein the robot includes an automatic toolchanger, allowing the surgeon to quickly interchange tools on therobotic arm.

A further objective of the present invention is to provide a roboticsurgical system that utilizes two robotic arms functioning in tandem sothat one robotic arm provides ultrasonic images to allow the secondrobotic arm to complete the desired surgical procedure.

Other objects and advantages of this invention will become apparent fromthe following description taken in conjunction with any accompanyingdrawings wherein are set forth, by way of illustration and example,certain embodiments of this invention. Any drawings contained hereinconstitute a part of this specification, include exemplary embodimentsof the present invention, and illustrate various objects and featuresthereof.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 illustrates one embodiment of the multi-axis robot along with anoperator station;

FIG. 2 illustrates a side view of one embodiment of the multi-axisrobot;

FIG. 3 illustrates an isometric view of one embodiment of theoscillating tool secured to the distal arm of a multi-axis robot;

FIG. 4 is an isometric end view of the embodiment illustrated in FIG. 3;

FIG. 5 is a side isometric view of the embodiment illustrated in FIG. 3;

FIG. 6 is a front isometric view of the embodiment illustrated in FIG.3;

FIG. 7 is an isometric view of an alternative embodiment of theoscillating tool secured to the distal arm of the multi-axis robot;

FIG. 8 is a front isometric view of an alternative embodiment of theoscillating tool secured to the distal arm of the multi-axis robot;

FIG. 9 is a front isometric view of an alternative embodiment of theoscillating tool secured to the distal arm of the multi-axis robot;

FIG. 10 is a partial section view illustrating one embodiment of theoscillating tool;

FIG. 11 is a partial section view of the embodiment illustrated in FIG.10;

FIG. 12 is a partial isometric view of the embodiment illustrated inFIG. 10 illustrating a scotch yoke mechanism for creating oscillatorymovement;

FIG. 13 is an isometric view of an alternative oscillating mechanismillustrated without the outer case;

FIG. 14 is a partial isometric view of the embodiment illustrated inFIG. 13;

FIG. 15 is a partial isometric section view of the embodimentillustrated in FIG. 13;

FIG. 16 is an isometric view of an alternative oscillating mechanismillustrated without the outer case;

FIG. 17 is a partial section view illustrating a cam mechanism forcreating the oscillating movement of the cutting tool;

FIG. 18 is a partial section view illustrating a cam mechanism forcreating the oscillating movement of the cutting tool;

FIG. 19 is a side view illustrating a robotic arm with an ultrasoundprobe and a display of the image generated;

FIG. 20 is a partial view of the embodiment illustrated in FIG. 19;

FIG. 21 is a side view illustrating one embodiment of a tool changesystem for use with a robotic arm;

FIG. 22 is an isometric view of one embodiment of the robotic armincluding an ultrasonic probe and an oscillating tool; and

FIG. 23 is a side view of one embodiment of the present system utilizingtwo robotic arms.

DETAILED DESCRIPTION OF THE INVENTION

While the present invention is susceptible of embodiment in variousforms, there is shown in the drawings and will hereinafter be describeda presently preferred, albeit not limiting, embodiment with theunderstanding that the present disclosure is to be considered anexemplification of the present invention and is not intended to limitthe invention to the specific embodiments illustrated.

Referring to FIGS. 1-23, a robotic surgical system 100 is illustrated.The robotic surgical system 100 generally includes a multi-axis robot 2,a tool 4 (oscillating tool assembly below) with an effector 5 on adistal end thereof, and an operator station 6. The tool 4 is preferablyan oscillating tool as more fully described below. The multi-axis robot2 includes a plurality of axes about which the oscillating tool 4 can beprecisely maneuvered and oriented for surgical procedures. In apreferred, but non-limiting, embodiment, the multi-axis robot includesseven axes of movement. The axes of movement include the base axis 202generally centered within the base 200 and about which the first arm 204rotates. The second axis 206 is substantially perpendicular to the firstaxis 202 and about which the second arm 208 rotates. The second arm 208includes the third axis 210 about which the third arm 212 rotates. Thethird arm 212 includes the fourth axis of rotation 214 which is orientedsubstantially perpendicular with respect to the first axis 202 andsubstantially parallel to the second axis 206. The fourth arm 216rotates about the fourth axis 214. The fourth arm 216 includes the fifthaxis 218 about which the fifth arm 220 rotates. The fifth arm 220includes the sixth axis 222 which includes the most available rotationabout the sixth axis 222 for the wrist 224 of the robot. The wrist 224carries the tool 4 and effector 5 and has a seventh axis of rotation 228for the cutting tool. The wrist 224 is at the distal end of the fiftharm 220. It should be noted that each axis of rotation provides anadditional freedom of movement for manipulation and orientation of thetool 4. It should also be noted that while the multi-axis robot 2 isonly illustrated with the tool 4, the preferred embodiment is capable ofchanging the effector to a variety of tools that are required tocomplete a particular surgery. Drives, not shown, are utilized to movethe arms into their desired positions. The drives may be electric,hydraulic or pneumatic without departing from the scope of theinvention. Rotational position can be signaled to a computer 230, aswith an encoder (not shown) associated with each arm 206, 208, 212, 216,220 and other components having an axis of rotation. In the preferredembodiment, the drives are in electrical communication with the computer230, and may further be combined with a telemanipulator, or pendant (notshown). The computer 230 is programmed to control movement and operationof the robot(s) 2 through a controller portion 231, and can utilize asoftware package such as Excelsius GPS™ from Globus. Alternatively,other software programming may be provided without departing from thescope of the invention. The computer 230 can have a primary storagedevice (commonly referred to as memory) and/or a secondary storagedevice that can be used to store digital information such as imagesdescribed herein. Primary and secondary storage are herein referred toas storage collectively, and can include one or both primary andsecondary storage. The system 100 may further include sensors positionedalong various places on the multi-axis robot 2, which provide tactilefeedback to the operator or surgeon 232. The computer 230 iselectrically connected or coupled to the multi-axis robot 2 in a mannerthat allows for operation of the multi-axis robot 2, ranging frompositions adjacent the robot to thousands of miles away. The computer230 is preferably capable of accepting, retaining and executingprogrammed movements of the multi-axis robot 2 in a precise manner. Inthis manner, skilled surgeons can provide surgical care in areas, suchas battlefields, while the surgeon is safe from harm's way. Thecontroller 231 can include a movement control input device 233, such asa joy stick, keyboard, mouse or electronic screen 306, see FIG. 19, thatcan be touch activated. The screen 306 can be part of the monitor 234.Tool change commands can be input using the screen 306.

Referring to FIGS. 3-12, various embodiments of the oscillating tool 4being utilized as an effector are illustrated. The oscillating toolassembly 4 can be used in surgical operations, such as spinal surgery,wherein bone, cartilage, disk, and other non-fibrous body material maybe removed, such as from the spine. The oscillating tool assembly 4 hasan output spindle 36 which is driven to rotate in both directions, orrotary oscillate about its axis 228. The spindle 36 supports a cuttingtool 38, which is driven by the spindle 36 to rotate partially in bothdirections with a limited range of rotation. Such oscillatory cutting iseffective for bone, cartilage, and disk removal by a shearing operation,while effective in minimizing damage to any fibrous material. If thecutting tool 38 inadvertently contacts fibrous material, such as anerve, during the cutting operation, the fibrous material is likely tobe oscillated due to the flexibility of the fibrous material withminimal shearing, thereby minimizing damage to the fibrous material.

FIG. 10 illustrates some internal components of the oscillating toolassembly 4. A power source may be provided by a battery supply 46oriented in the housing 32. The battery supply 46 may be charged orrecharged by the multi-axis robot 2. Electronics 48 are provided in thehousing 32 for controlling the operations of the tool assembly 4. Thepower switch (not shown) may be remotely operated via the computer 230,telemanipulator, or pendant. A plurality of indicator lamps 50 may beprovided on the housing 32 and illuminated by LEDs for indicatingoperational characteristics of the tool assembly 4, such as the state ofcharge of the battery supply 46. Alternatively, the tool 4 maycommunicate wirelessly via Bluetooth, ZIGBY chip or the like to thecomputer 230, whereby the signal is visible on the monitor 234 eitherlocally and/or remotely.

A motor 52 is mounted in the housing 32 for providing a rotary input.The motor 52 is powered by the battery supply 46 when controlled by theelectronics 48. The motor 52 drives a transmission 54 for convertingcontinuous rotary motion from the motor 52 to rotary oscillation to thespindle 36. The spindle 36 is journalled in the housing 32 and driven bythe transmission 54. The spindle 36 is preferably straight, but may beangled relative to the housing 32 as depicted in FIGS. 10-12 forspecific operations. Cooling fins, or a cooling fan (not shown), may beattached to or near the motor 52 for cooling the motor 52 and/or thetool assembly 4.

Referring now to FIGS. 11-12, the motor 52 drives an eccentric drive 56.The eccentric drive 56 includes a roller 58 supported to rotate upon thedrive 56, which is offset from an axis 60 of the motor 52. Thus,rotation of the eccentric drive 56 causes the roller 58 to revolve aboutthe axis 60. The eccentric drive 56 also includes a counter-balance 62offset from the axis 60, opposed from the roller 58, to counter-balancethe transmission 54 and to minimize unwanted vibrations. Thecounter-balance 62 can be formed integrally with the eccentric drive 56according to at least one embodiment. The counter-balance 62 may includean additional weight according to another embodiment. Alternatively, theroller 58 may be a pin. A guide, illustrated herein as a pair of pins64, 65, is supported in the housing 32, generally perpendicular to themotor axis 61. Alternatively, a single rail (not shown) may be utilizedwithout departing from the scope of the invention. A shuttle 68 isprovided on the guide 64 for reciprocating translation upon the guide64. The shuttle 68 includes a channel 70 that is generally perpendicularto the guide 64. The channel 70 receives the roller 58 of the eccentricdrive 56. The channel 70 cooperates as a follower for permitting theroller 58 to translate along a length of the channel 70 while drivingthe shuttle 68 along the guide 64. The guide 64 may utilize bearingsand/or rollers or the like to reduce friction.

Referring again to FIGS. 10-12, a gear rack 72 is formed upon theshuttle 68. The gear rack 72 is formed generally parallel to the spindle36. A pinion gear or burr gear 74 is mounted to the spindle 36 inengagement with the gear rack 72, thereby providing a rack-and-pinionmechanism for converting the reciprocating translation of the shuttle 68to rotary oscillation of the spindle 36. A pair of bearing assemblies 76may also be provided in the housing for providing bearing support to thespindle 36. The transmission 54 may include any additional gearsets, asis known in the art, to vary speed or torque. According to oneembodiment, a spur gear may be added to a motor output shaft to multiplyspeed of the roller 58.

The eccentric drive 56 and shuttle 68 cooperate as a Scotch-yokemechanism for converting continuous rotary motion to linearreciprocating motion. Although the Scotch-yoke mechanism is illustrated,any mechanism for converting rotary motion to reciprocation can beemployed, such as a crank-and-slider mechanism, or the like. It shouldalso be noted that, in some embodiments, the spindle 36 and spindle tube37 (FIGS. 6, 7) are removable and replaceable from the remainder of thehousing. In this manner, cutters or gear ratios that provide more orless oscillation can be easily changed to suit a particular need.

Referring to FIGS. 8 and 9, alternative embodiments of the oscillatingtool assembly 4 are illustrated. In these embodiments, the electricmotor 52 and transmission assembly 54 are oriented at about a rightangle with respect to the spindle 36. This construction may provideadvantages for types of operations by shortening the distance from theend of the wrist 224 to the end of the spindle 36.

Referring to FIGS. 13-15, an alternative embodiment of the oscillatingtool 104, having the housing omitted for clarity is illustrated. Thetransmission 154 is positioned in the housing 132 and operably couplesthe shaft 136 to the motor 152, and is operable to convert thecontinuous rotary motion of the motor shaft 163 (FIG. 15) of the motor152 to oscillating rotary motion of the shaft 136. By oscillating rotarymotion, it is meant that the shaft 136 will rotate a portion of acomplete revolution first in one rotation direction then in anotherrotation direction; say first counterclockwise, then clockwise, thencounterclockwise again and so on. To effect this movement, thetransmission 154 comprises two sections. The first section is designatedgenerally 161, and is operable to convert the rotary motion of the shaft163 of the motor 152 to reciprocating linear motion of a portionthereof, and the second section is designated generally 162, and isoperable to convert that reciprocating motion to oscillating rotarymotion.

In the illustrated embodiment, the transmission section 154 is in theform of a Cardan mechanism that utilizes an internal ring gear 164 andan external pinion gear 165, with the pinion gear 165 being positionedinside of and having its external gear teeth in engagement with theinternal gear teeth of the ring gear 164. The gear ratio of the ringgear 164 to pinion gear 165 is 2:1. The ring gear 164 is suitably fixedin the housing 32 to prevent its motion relative to the housing 32. Thepinion gear 165 is suitably mounted to a crank arm 166, which in turn issecured to the shaft 163 of the motor 152 and is offset from the axis ofrotation of the shaft 163, whereby the pinion gear 165 revolves aboutthe axis of rotation of the shaft 163 while inside the ring gear 164.Preferably, the crank arm 166 has a counterweight 167 opposite of wherethe pinion gear 165 is mounted to the crank arm 166. In a Cardanmechanism, one point on the pinion gear will move linearly in areciprocating manner within the ring gear associated therewith. In theillustrated embodiment, the path of movement of this point is timed tomove in a generally transverse plane relative to a portion of thetransmission 154. Secured to the pinion gear 165, preferably in anintegral manner, is a driver arm 169 that extends forwardly of the ringgear 164 for receipt in a follower 170 to effect movement of thefollower 170 in response to movement of the driver arm 169. The follower170 is suitably mounted in the housing 32 in a manner to permit itspivoting movement about an axle 171. The transverse linear movement of aspot on the pinion gear 165 is generally transverse to the longitudinalaxis of elongate slot 174 in the follower 170. The axle 171 is suitablymounted in bearing supports 173 that are in turn suitably mounted to thehousing 32. While only one bearing support 173 is shown, it is preferredthat each end of the axle 171 have a bearing 173 associated therewith.It is to be understood that the axle 171 could utilize the follower 170as a bearing for rotation of the follower 170 about the axle 171, andhave the axle 171 mounted to the housing 32 in a fixed manner. Thedriver arm 169 is received within the elongate slot 174 for effectingmovement of the follower 170 in a rotary oscillating manner. Thefollower 170 moves in an oscillating rotary manner about the axis 186 ofthe axle 171. When a portion of the driver arm 169 is moving in itslinear path, portions of the arm 169 engage sides of the slot 174 toeffect movement of the follower 170 in response to movement of thedriver arm 169. In the illustrated structure, the driver arm 169 isoffset to the outside diameter of the pinion gear 165, and thus itscentral axis does not move in a linear path, but will move in a seriesof arcs that are elongated in a horizontal plane and reduced in thevertical direction. This back-and-forth and up-and-down movement isaccommodated by constructing the slot 174 to be elongated, as best seenin FIG. 15. As the driver arm 169 moves in its path, it affectsoscillating rotary motion of the follower 170 about the axle 171. Twocounterclockwise and two clockwise oscillations of the cutter 38 areaffected, and four oval paths are traversed for each revolution of thepinion gear 65 within the ring gear 164. The follower 170 is providedwith a sector gear 176 that is operably coupled to a gear 177 secured tothe shaft 136. As the follower 170 moves, the shaft 136 moves inresponse thereto by engagement between the gears 176 and 177. Becausethe follower 170 moves in a rotary oscillating manner, the shaft 136also moves in a rotary oscillating manner. The components of thetransmission sections 161, 162 are configured relative to one anothersuch that, when the rotary oscillating movement changes direction at theshaft 136, the applied torque by the motor 152 would be high; while atthe center of one oscillation, the applied torque by the motor 152 wouldbe lower. This assists in providing a high starting torque for thecutter 38 to reverse rotation direction.

Referring to FIGS. 16-18, another alternative embodiment of theoscillating tool for use with the robotic surgical system 100 isillustrated. The alternative oscillating tool assembly 200 includes amotor 202 mounted in a housing 204. The motor 202 drives a cam mechanism206 for continuous rotation. The cam mechanism 206 has four distinct camprofiles 208, 210, 212, 214 stacked axially from the motor 202. Each ofthe cam profiles 208, 210, 212, 214 is illustrated schematically inFIGS. 17-18. A follower mechanism 216 is mounted for rotation in thehousing 204. The follower mechanism 216 has four follower profiles 218,220, 222, 224, each for cooperating with one of the cam profiles 208,210, 212, 214, as also illustrated in FIGS. 16-18. A spindle 226 isprovided in the housing 204 with bearing support. The cam mechanism 206and the follower mechanism 216 cooperate as a transmission 229 forconverting one rotation of the cam mechanism into two rotaryoscillations of the follower mechanism 216.

The electric motor 202 spins the cam mechanism 206 continually in onedirection, which is clockwise in FIGS. 17-18. The cam profiles 208, 210,212, 214 engage the follower profiles 218, 220, 222, 224 at two contactpoints at all times. At one contact point, the cam mechanism 206 pushesthe follower mechanism 216 to rotate. At the other contact point, thecam mechanism 206 prevents the follower mechanism 216 fromover-rotating. The profiles 208, 210, 212, 214 on the cam mechanism 206work together to cause the follower mechanism 216 to rotationallyoscillate in two directions. For the depicted embodiment, each of thefour cam profiles 208, 210, 212, 214 consists of two symmetrical lobes,which causes the follower mechanism 216 to make two completeoscillations (back and forth twice) for every complete revolution of themotor 202. The cam mechanism 206 could also be designed asymmetrical,and/or so that it causes the follower mechanism 216 to make any numberof oscillations, such as one, or more than two, per motor revolution.

In FIG. 17, the second cam profile 210 contacts the second followerprofile 220 for preventing over-rotation of the follower mechanism 216,while the fourth cam profile 214 drives the fourth follower profile 224.In FIG. 18, the second cam profile 210 contacts the second followerprofile 220 for driving the follower mechanism 216, while the third camprofile 212 engages the third follower profile 222 to preventover-rotation of the follower mechanism. In FIG. 17, the first camprofile 208 contacts the first follower profile 218 for preventingover-rotation of the follower mechanism, while the third cam profile 212drives the third follower profile 222, thereby reversing directions. InFIG. 18, the first cam profile 208 contacts the first follower profileto prevent over-rotation of the follower mechanism 216, while the fourthcam profile 214 drives the fourth follower profile 224. The process isrepeated at FIG. 17.

Referring to FIGS. 1 and 19-23, an alternative embodiment isillustrated. In this embodiment, the robotic surgical system 100generally includes one or two multi-axis robot(s) 2, an ultrasoundimaging system 300, an effector such as an oscillating tool 4, and anoperator station 6. Typically, a surgeon would utilize fluoroscopy orfluoroscopy in combination with computer tomography (CT) scans or thelike in order to perform surgery on the spine or other skeletal parts.The CT scans are performed prior to the surgery so the surgeon canidentify landmarks within the patient 308 and attempt to align thefluoroscopic image with the CT scan image to perform the surgery.However, the fluoroscopic images are often difficult to align becausethe patient is in a different position, causing distortion in thefluoroscopic imaging etc. Thus, in order to provide real time images tothe surgeon 232, one of the robot(s) 2 may be fitted with an ultrasoundimaging probe 302. The ultrasonic imaging probe 302 is electricallyconnected to an imaging system electronic controller 304 provided in thecomputer 230 which allows the operator to project the real-time imagesupon of monitor 234 and ensure proper overlay of the ultrasound imagewith the CT scan. The CT scan image(s) and ultrasonic image(s) can bestored in and recalled from the computer 230 storage and displayed onthe monitor 234. The monitor 234 may be positioned in the operatorstation 6 and/or within the operating room 310. This construction allowsthe operator 232 to take fluoroscopic images without subjecting himselfor herself to the radiation, while still allowing landmarks within thepatient 308 to be closely identified and located for storage within theoperator's station for use in the surgery. Thus, the operator cancalibrate the robots positioning to correspond to the real-timeultrasonic image for completing the surgery. Afterwards, the operatorcan change the ultrasound probe 302 for a surgical instrument(s) tool 4with effector 5 needed for the surgery in progressive order so that thetool(s) can be precisely maneuvered and oriented for surgicalprocedures. Springs or the like may also be utilized to control theamount of force that is used to push against the patient with the probe,e.g., the probe 302 can be spring loaded to reduce the risk of hardcontact with a patient during probe movement.

Referring to FIG. 20, the wrist 223 portion of the robot carries theultrasound probe 302. The ultrasound probe 302 is removably secured tothe wrist 223 to allow probes or tools having different configurationsto be interchanged by the robot upon command from the operator 232through the computer 230 and coupled operator input controller 231 thatallows the computer to know what the length 312 as well as the diameter314 of the probe or tool 4 and effector 5 are. Thus, the robot can makefast approaches to the patient and slow down when the probe 302 or tool4 is close to the patient, and still touch the patient in a softcontrolled manner. In this manner, the computer 230 can also alter thethree-dimensional positioning of the robot to correspond to the tool orprobe size in relation to the real-time images.

Fiducial point devices 351 can be used to assist in determining theposition of a tool 4 relative to a patient 308, and to assist inoverlaying the various images, like the CT scan and ultrasound images.Typically for orthopedic surgery, fiducial point devices 351 areattached to a bone as with a screw. Such fiducial point devices areavailable from Northern Digital, Inc.

FIG. 21 illustrates an embodiment of the present device that includes anautomatic tool changer 316. The automatic tool changer 316 isconstructed and arranged to allow the tool 4 with effector 5 to bechanged by the robot 2 in response to a command from the computer 230,input preferably by the operator 232. In operation, the wrist 224 ofrobot 2 is positioned in a predetermined place. A tool arm 318 rises orrotates to engage the tool in the wrist 224 which is released. The toolarm 318 then lowers to remove the tool 4 and rotates to position analternative tool under the wrist 224. The tool arm 318 rises to positionthe new tool within the wrist 224 where the wrist engages the tool 4.The tool arm 318 may then either retain the removed tool or place itonto a carrousel or conveyor 320, which may include any number of tools.Each tool 4 is provided with a tapered or otherwise shaped shank 322which is shaped to cooperate with a cavity within the wrist 224 toprovide repeatable positioning. In at least one embodiment, each tool isalso provided with a tang 324 which cooperates with a drawbar or drawmechanism (not shown) within the wrist 224 to pull the tool into thewrist in a controlled and repeatable manner. A tool changer such as theMC-16R, QC-11 and QC-21 made by ATI can also be used instead of thedrawbar type just described. As stated earlier, the length and diameterof each tool is retained within the computer 230 in the operator'sstation 6 so that positioning of the robot 2 arms is altered tocorrespond to each tool. In this manner, one tool can be utilized andquickly changed to the next needed tool while still utilizing thecalibration and positioning provided from the ultrasound imaging. In atleast one embodiment, the robot can be configured to rotate the wrist ofthe 223 of the robot to measure the moment of the tool as a second checkthat the proper tool is inserted into the wrist.

Referring to FIG. 22, an alternative embodiment is illustrated. In thisembodiment, the ultrasound probe 302 is secured to a side or othersurface of the wrist 223. This construction allows the wrist 223 to besimply rotated to touch the ultrasound imaging probe 302 onto thepatient 308 to provide imaging and/or repositioning of the wrist 223with respect to the image. Once the image and positioning are checked orrechecked, the wrist 223 can be rotated to use the tool also carried bythe wrist. In this embodiment, the computer 230 keeps track of both thelength 312 and diameter 314 of the ultrasound probe 302 and tool 4 sothat precise locations are maintained when switching from the probe tothe tool or between tools.

Referring to FIG. 23, an alternative embodiment is illustrated. In thisembodiment, the system is provided with two or more robots 2 which workin unison and communicate positioning with the operator station 6 andeach other to prevent collisions and coordinate actions. As illustrated,one robot 2 utilizes the ultrasound imaging probe 302, while the otherrobot utilizes the tool 4. In this manner, images can be takensimultaneously with operation of the cutting, drilling or other tools 4.This construction allows positioning corrections or other manipulationsof the tools to be made as the surgery is occurring. It should be notedthat the automatic tool changer may be used in conjunction with this orany other embodiment disclosed herein to add versatility to the system.It should also be noted that while the ultrasound tool is illustrated ashaving a different trajectory than that of the robot with the tool, thesecond robot will preferably direct the ultrasound on an intersectingtrajectory with the cutting tool.

The present invention is better understood by a further description ofits operation. A patient 308 is scheduled for surgery. In preparation, afirst image of the surgical sight is created, for example, with a CTscan. Preferably, the first image is three-dimensional. The first imageis digitally stored in the computer 230. At least one and preferably aplurality of fiducial point devices 351 are secured to the patient 308and are included in the first image. The patient 308 is prepared forsurgery and moved to the operating room 310. At least one robot 2 islocated in the operating room, along with an automatic tool changer 316positioned adjacent the robot(s) 2. The patient's surgical sight isexposed to the robot(s) 2. An ultrasound probe 302 is mounted to a robot2, and a second digital image is created of the surgical sight andstored in the computer 230. The first and second images are overlaid bythe computer 230 using the fiducial point device(s) 351 as acoordinating reference. At least the second image of the surgical sightin displayed on the screen 306 of the monitor 234, showing the surgicalsight in real time at least at the beginning of surgery. Preferably,both the first and second images are simultaneously displayed on themonitor 234 and are both preferably three-dimensional images. If tworobots 2 are used, a continuous second image can be displayed in realtime or, if one robot 2 is used, the ultrasound probe can be usedintermittently as selected by the operator 232 as, for example, betweentool 4 changes. In a preferred embodiment, when an ultrasound probe isbeing operated during use of a tool 4, the ultrasound probe 302 ispointed in a direction to sense the effector 5 of the tool 4 and displayit in the second image.

The computer 230, the operator controller 231, the monitor 234, screen306, ultrasound probe 302 and robots 2 are operably coupled together toeffect the various operations of each. While a single computer 230 isshown, it is to be understood that multiple computers can be incommunication with one another to form a computer 230. For example, aremote computer can be coupled to a local computer through an internetserver to form the computer 230. An operation control system includesthe imaging control system 304, controller 231 and possibly screen 306,depending on its construction.

All patents and publications mentioned in this specification areindicative of the levels of those skilled in the art to which theinvention pertains. All patents and publications are herein incorporatedby reference to the same extent as if each individual publication wasspecifically and individually indicated to be incorporated by reference.

It is to be understood that while a certain form of the invention isillustrated, it is not to be limited to the specific form or arrangementherein described and shown. It will be apparent to those skilled in theart that various changes may be made without departing from the scope ofthe invention, and the invention is not to be considered limited to whatis shown and described in the specification and any drawings/figuresincluded herein.

One skilled in the art will readily appreciate that the presentinvention is well adapted to carry out the objectives and obtain theends and advantages mentioned, as well as those inherent therein. Theembodiments, methods, procedures and techniques described herein arepresently representative of the preferred embodiments, are intended tobe exemplary, and are not intended as limitations on the scope. Changestherein and other uses will occur to those skilled in the art which areencompassed within the spirit of the invention and are defined by thescope of the appended claims. Although the invention has been describedin connection with specific preferred embodiments, it should beunderstood that the invention as claimed should not be unduly limited tosuch specific embodiments. Indeed, various modifications of thedescribed modes for carrying out the invention which are obvious tothose skilled in the art are intended to be within the scope of thefollowing claims.

What is claimed is:
 1. A method of performing a surgical procedure usinga multi-axis robot, the method including: securing at least oneradiopaque fiducial point device to a patient; creating a first digitalimage and storing it in a computer, said first image including a portionof a patient and the at least one fiducial point device visible in thefirst image; positioning at least one multi-axis first robot adjacent apatient, said robot having a plurality of interconnected arms with onesaid arm being mounted to a base, said arms being movable relative toone another, one said arm being a distal arm and having a tool holderconfigured to releasably and alternately retain at least one surgicaltool and an ultrasound probe, said computer being electrically coupledto the robot and operable to control movement of the arms in response tocommands supplied to the computer from a controller electrically coupledto the computer; creating at least one second image of at least saidportion of a patient during surgery with said ultrasound probe securedto said distal arm of said multi-axis first robot and storing said atleast one second image in the computer; overlaying the first image andthe second image for viewing and displaying said overlaid first andsecond images on a monitor coupled to the computer, said overlaid firstand second images including at least a portion of a surgical sight ofthe patient and the at least one fiducial point device, said computerbeing operable to adjust the position of the first image to the secondimage using the at least one fiducial point device for alignment withrespect to each other; operating the at least one robot with thecontroller; and operating on the patient with the multi-axis first robothaving the surgical tool attached to the tool holder while viewing theoverlaid first and second images.
 2. The method of performing a surgicalprocedure using a multi-axis robot as claimed in claim 1 including atool changer positioned within reach of the distal arm of the firstmulti-axis robot, a tool change rack positioned adjacent the toolchanger and operable to hold a plurality of surgical tools, each toolconfigured to be secured to the tool holder in response to a commandfrom the controller, wherein the distal arm is positioned relative tothe tool changer to allow the tool changer to position a surgical toolfrom the tool change rack in position for securement by the tool holderto the distal arm.
 3. The method of performing a surgical procedureusing a multi-axis robot as claimed in claim 2 wherein the tool changeris constructed and arranged to remove the surgical tool from the toolholder and place the surgical tool into the tool change rack.
 4. Themethod of performing a surgical procedure using a multi-axis robot asclaimed in claim 3 wherein surgical tool selection is controlled by thecomputer to position a surgical tool for attachment to the distal armvia the tool changer.
 5. The method of performing a surgical procedureusing a multi-axis robot as claimed in claim 1 including a secondmulti-axis robot positioned adjacent the patient, said second robot saidrobot having a plurality of interconnected arms with one said arm beingmounted to a base, said arms being movable relative to one another, onesaid arm being a distal arm and having a tool holder configured toreleasably and alternately retain at least one surgical tool or anultrasound probe; positioning the second multi-axis robot adjacent thepatient, said computer being electrically coupled to the robot andoperable to control movement of the second robot arms in response tocommands supplied to the computer from a controller electrically coupledto the computer; creating at least one real-time image of at least saidportion of a patient during surgery with said ultrasound probe securedto said distal arm of said second multi-axis robot and overlaying thefirst image and the real-time image for viewing and display on themonitor coupled to the computer, said overlaid first and real-timeimages including at least the portion of a surgical sight of the patientand the at least one fiducial point device, said computer being operableto adjust the position of the first image to the real time image usingthe at least one fiducial point device for alignment with respect toeach other.
 6. The method of performing a surgical procedure using amulti-axis robot as claimed in claim 5 including operating on thepatient with the multi-axis first robot having the surgical toolattached to the tool holder while providing real-time images to thecomputer for viewing with the second multi-axis robot having theultrasound probe secured thereto.
 7. The method of performing a surgicalprocedure using a multi-axis robot as claimed in claim 5 wherein thecomputer is constructed and arranged to further display a tool path ofsaid first multi-axis robot on the overlaid first and second images. 8.The method of performing a surgical procedure using a multi-axis robotas claimed in claim 5 wherein the first image is a three dimensionalimage, the computer and the second multi-axial robot in electricalcommunication to align the plane of the second image with the firstimage so that the combined image is shown as a two dimension alignedplane image.
 9. The method of performing a surgical procedure using amulti-axis robot as claimed in claim 5 including a plurality of thefiducial markers.
 10. The method of performing a surgical procedureusing a multi-axis robot as claimed in claim 5 wherein the tool changeris positioned within reach of the distal arm of the second multi-axisrobot, the tool change rack positioned adjacent the tool changer andoperable to hold a plurality of surgical tools, each tool configured tobe secured to the tool holder of the second multi-axis robot in responseto a command from the controller, wherein the distal arm of the secondmulti-axis robot is positioned relative to the tool changer to allow thetool changer to position a surgical tool from the tool change rack inposition for securement by the tool holder to the distal arm of thesecond multi-axis robot.
 11. The method of performing a surgicalprocedure using a multi-axis robot as claimed in claim 10 wherein thetool changer is constructed and arranged to remove the surgical toolfrom the tool holder of the second multi-axis robot and place thesurgical tool into the tool change rack.
 12. The method of performing asurgical procedure using a multi-axis robot as claimed in claim 11wherein the tool change rack is controlled by the computer to position asurgical tool for attachment to the distal arm of the second multi-axisrobot via the tool changer.
 13. The method of performing a surgicalprocedure using a multi-axis robot as claimed in claim 1 wherein thefirst image is a computerized tomography image.
 14. The method ofperforming a surgical procedure using a multi-axis robot as claimed inclaim 2 wherein the computer includes the length and diameter of thesurgical tools in a computer memory.
 15. The method of performing asurgical procedure using a multi-axis robot as claimed in claim 14wherein the length and memory of the surgical tool is utilized to alterthe tool path of the first multi-axis robot.
 16. The method ofperforming a surgical procedure using a multi-axis robot as claimed inclaim 2 wherein each surgical tool is provided with a shaped shank, theshank being shaped to cooperate with a shaped cavity provided in thedistal arm of the first multi-axis surgical robot.